On the ADE desktop app, how can you change the e-mail associated with the ID, after you have changed this associated e-mail on your account on the Adobe website?

I have changed the e-mail associated with my Adobe ID on my account on the Adobe website. I now need to effect the same change on the Desktop app. I tried to do this using the dropdown Help menu, which brought up a window asking me to authorise the change using the old e-mail address. This didn't work, and it did not allow me to change the e-mail address to the new one. How can I proceed?